When I was in grad school 20 years ago I was living on about $10k per year. Not just apartment, car, food, etc, but I also had to pay tuition and books. And I still managed to sock away a few bucks into Monetta Fund and Low Price Stock Fund (and there was another, but I can't remember the name now). My internet was dial-up, and I had no cable TV.

Not that I'm suggesting a family of four could have gotten by on that, even then. But this notion you need 6 figures is silly.